The present invention relates to storing and loading spools to be used by reel-up machines that wind webs, e.g., tissue, onto successive spools to form web rolls. In particular, the invention relates to multiple elevations of spool storage rails associated with a reel-up.
Present reel-up machines use either a crane, or an automatic loading system, to move reel spools from a single upper elevation of storage rails to the primary arms of a reeling machine or into a similar pre-start spool position. U.S. Pat. Nos. 3,586,253 and 6,047,916, disclose exemplary reel-up machines having a single pair of rails to move and store empty reel spools across the upper elevation of a reel-up machine. The rails for the empty spools are arranged on a single elevation above the lower portion of the reel-up machine that winds a web onto a spool to form a web roll. When the web is completely wound onto a spool and the web roll is discharged from the reel-up machine, the spool is removed from the roll and processed. The spool is lifted to a single elevation of a pair of spool rails by a crane or other lifting system. A train of empty spools roll along the single elevation upper rails and towards the inlet of the reel-up machine.
Conventionally, the individual spool at the discharge end of the rails nearest the reeling station (reel drum) was the only spool that could be selected and moved down to wind the next roll of moving web. The conventional reel-up paper machine with single elevation upper rails is limited in that it can only load the one empty spool that is at the discharge end of the upper spool rail elevation. This conventional reel-up paper machine does not allow for one of a plurality of empty spools to be selected for moving into the winding or reeling station to wind the web.
Some reel-up machines require the segregation of reel spools, either because some spools go to different processes, are intended to run different grades of material, or may be in better or worse condition than the others and only used when the need arises. Some spools may be plain (no cover or core), some spools may have rubber covers, some spools may be core-type spools for use with slitters or for export rolls and have different numbers of cores, and some may be different diameters. There is a need to select between a plurality of available spools to be used to wind a web roll.
Mills operating reel-up machines with a single elevation of spool storage rails must plan properly with the production paper roll runs to make sure the correct reel spools are in the reel-up machine and, in particular, inserted into the pre-start position, usually primary arms, from the spool loader at the correct time to ensure that desired changes in the machine take place. Historically, when a spool (other than the spool naturally next in line on the rails) has been needed, the desired spool is stored at an off-machine location and the loading process is scheduled so that the spool is loaded into the machine at exactly the right time and position. At the same time, other empty reel spools may be taken and stored at a different location (rather than being temporarily stored on the upper rails). These spool changing situations require more operator involvement, more advanced planning and more movement of reel spools from one position to another.